SAN FRANCISCO—No wonder Jim Harbaugh treats Colin Kaepernick as if they were created from the same rib.

Kaepernick is a clone of Harbaugh, at least in matters that mean the most this time of year. Like his head coach, the San Francisco 49ers quarterback doesn’t care much about what others think. In truth, both seem their happiest when they have their audience frowning, fuming.

It’s that snarling, raised-finger attitude that could nudge the Niners over the hump that last season proved too difficult to vault. In January 2012, Kaepernick was on the sideline, squeezing the clipboard so tightly it’s a wonder the thing didn’t begin to leak blood.

Now, as the 49ers saunter into the NFC Championship game for the second time in 12 months, Kaepernick has to be the most thrilling individual to still be upright in these playoffs. And that’s saying something considering these playoffs have teemed with more stop-the-breath moments than a Quentin Tarantino script.

As if we needed another reminder that this remains the best football weekend of the year, there was Kaepernick turning his first postseason appearance into a vision that won’t be replicated in a long while. All he did was outgun and outplay Aaron Rodgers, the reigning NFL MVP, a Super Bowl champion and Cal star who desperately wanted to prove the 49ers wrong for passing on him in the 2005 NFL Draft.

With the second-year Kaepernick mastering the option—with him running like the wind, with him whipping passes through tiny seams, with him yapping and taunting and mocking a defense that reacted as if it had never witnessed such audacity—San Francisco beat the Green Bay Packers, 45-31, in a divisional playoff game that for one half was bitterly equal.

The 49ers have picked a fine time to unearth a sizzling groove. After dropping two of their final five regular season games and giving up a mountain of points during a scattered stretch, the Niners pieced together an extraordinary night at giddy Candlestick Park.

It began with Kaepernick throwing a pick-six—Sam Shields returned an interception 52 yards for a 7-0 Packers’ lead—and it ended with the Niners posting a shocking 579 yards of offense. Kaepernick’s feet were responsible for 181 of them (a quarterback playoff record that was highlighted by two rushing touchdowns), he passed for another 263 yards (completing 17-of-31 attempts for another two TDs) and led a string of offensive series that had even old-timers in Montana jerseys picking their jaws up off the cement floor.

Where to begin? Maybe earlier in the week when Kaepernick wore a Milwaukee Brewers cap during interviews with the media. He spent the first four years of his life in Wisconsin before moving to California, and as all Packers fans know, the DNA never really leaves the system. There were some loud mumbles in these parts about his choice of lids, but Kaepernick merely rolled his eyes.

(His eye roll is something, by the way. A person could break a blood vessel trying to imitate it. Parents everywhere must be hoping their children paid more attention to Kaepernick’s scampering feet than those eyeballs.)

So it was hardly shocking to see Kaepernick late in the first half of a tie game, on a third-and-9 from the Green Bay 24, scramble up the gut for 15 yards, faking out M.D. Jennings with those eyes before running full-on into the safety. Kaepernick stood there jawing, talking trash, earning a taunting penalty.

What sophomore quarterback does such a thing? A sophomore quarterback who feasts on nails, apparently.

“You won’t find a tougher player out there,” said San Francisco running back Frank Gore. “He woke up a few people tonight.”

Two plays later, Kaepernick threw a pass as crisp as a brand-new Benjamin, a 20-yarder that Michael Crabtree somehow snagged in the end zone even though Shields had Crabtree covered as tight as second skin. The chemistry between Kaepernick and Crabtree is something to behold. This score put the 49ers up 21-14. Crabtree finished the night with 119 yards receiving, two TDs and a stutter move that could turn a coin on its head.

Then there was this: Game tied 21-all, 2:11 left in the half, Kaepernick spies a seam, keeps the ball, leaves vapors for 19 yards until the only place to go is the Packers’ sideline, where he finishes the play yapping at green-coated staff.

Or this: On a play most everyone in the house knew was a simple handoff, Kaepernick instead ran off right tackle, split the Green Bay defense and flew 56 yards into the end zone. There he casually flipped aside the ball and posed on the red carpet for kneeling photographers, many of them caught as unaware as the rest of us.

It was such an unexpected turn of events, this play that made it 31-24, this wild unveiling of a quarterback who wasn’t handed the reins until midseason, after underwhelming starter Alex Smith suffered another alarming concussion.

Harbaugh’s gamble to move Kaepernick from clenched clipboard holder to unquestionable leader seems beyond reasonable now. It couldn’t possibly backfire, not with Kaepernick obliterating the icy pressure of third downs.

He didn’t just keep up with Rodgers, the cool veteran who’s been known to whip the playoffs into his own personal playground. Rodgers was hindered by a stodgy pass-centric offense and a non-existent running game. The 49ers defense rarely blitzed but instead, especially in the second half, prevented the Packers from opening up the field. Rodgers completed 26 of 39 passes for 257 yards and two touchdowns, was intercepted once and never seemed comfortable in the pocket.

Rodgers’ second half began with him getting stiff-armed onto his backside, with linebacker Patrick Willis breaking through blocks and bullying the line. If Kaepernick has a special kind of attitude, his defense takes it to a whole different level.

Defensive end Justin Smith returned from a triceps injury with a newfound energy, playing the entire game. This is the sort of whole and healthy defense that mimics Harbaugh’s intensity, but now his quarterback is bringing a forceful strength as well.

"I joke with him all the time," Willis said of Kaepernick. "I say you've got to be one of the biggest and strongest quarterbacks I've seen. But he plays the position like a true quarterback. And that's what it's going to take."

Deep in the fourth quarter, with the game tilting in a direction few saw coming, Kaepernick had the wherewithal to draw the Packers offsides. Only those who could see the quarterback up close know for sure, but something tells us this play came with a side dish of yapping, and possibly some eye rolls.